Adjusting custom 2D transform gizmos to work with rotated shapes

I am trying to coding 2D transform gizmos with Rotate and Scale options. There are only two button. One is for rotate the object and another one is for scale the object in local space:

https://gfycat.com/celebratedpleasantharborporpoise

If rotation z (angle) of the target shape is equal to 0, then there is no problem. But if I rotate the object, then local scaling is not working correctly (As you can see in gif).

My Code:

 using UnityEngine;
 
 public class Test : MonoBehaviour
 {
     //Shape
     [Header("Shape")]
     public Transform shapeTransform;
 
     //Rotate
     [Header("Rotate")]
     public RectTransform rotateButtonRectTransform;
     private Vector3 rotateButtonDragOffset;
     private bool rotateButtonDown;
 
     //Scale
     [Header("Scale")]
     public RectTransform scaleButtonOriginRectTransform;
     public RectTransform scaleButtonRectTransform;
     public float scaleMultiplier = 0.005f;
     private Vector3 scaleButtonDragOffset;
     private Vector3 oldScale;
     private Vector3 scaleButtonPosition;
     private bool scaleButtonDown;
 
     //General
     public RectTransform handleTransform;
 
     public void OnRotateButtonDown()
     {//Firing by EventTrigger
         rotateButtonDragOffset = rotateButtonRectTransform.position - Input.mousePosition;
         rotateButtonDown = true;
     }
 
     public void OnRotateButtonUp()
     {//Firing by EventTrigger
         rotateButtonDown = false;
     }
 
     public void OnScaleButtonDown()
     {//Firing by EventTrigger
         scaleButtonDragOffset = scaleButtonRectTransform.position - Input.mousePosition;
         oldScale = shapeTransform.localScale;
         scaleButtonPosition = scaleButtonRectTransform.position;
         scaleButtonDown = true;
     }
 
     public void OnScaleButtonUp()
     {//Firing by EventTrigger
         scaleButtonDown = false;
         scaleButtonRectTransform.position = scaleButtonPosition;
     }
 
     private void Update()
     {
         //Rotate
         if (rotateButtonDown)
         {
             Vector3 targetPosition = Input.mousePosition + rotateButtonDragOffset;
             Vector3 pos = Vector3.Normalize(targetPosition - handleTransform.position);
             handleTransform.eulerAngles = new Vector3(0f, 0f, Mathf.Atan2(-pos.x, pos.y)) * Mathf.Rad2Deg;
 
             //Set rotation of shape
             var eulerAngles = shapeTransform.eulerAngles;
             eulerAngles.z = handleTransform.eulerAngles.z;
             shapeTransform.eulerAngles = eulerAngles;
         }
 
         //Scale
         if (scaleButtonDown)
         {
             scaleButtonRectTransform.position = Input.mousePosition + scaleButtonDragOffset;
 
             Vector3 dif = scaleButtonPosition - scaleButtonRectTransform.position;
 
             Vector2 scale = new Vector2(
                 oldScale.x + (dif.x * scaleMultiplier),
                 oldScale.y + (-1f * (dif.y * scaleMultiplier))
                 );
 
             //Set scale of shape
             shapeTransform.localScale = new Vector3(scale.x, scale.y, 1f);
         }
 
         //Scale and rotate gizmo
         ScaleAndRotateGizmo();
     }
 
     private void ScaleAndRotateGizmo()
     {
         var distance = Vector3.Distance(scaleButtonOriginRectTransform.position, scaleButtonRectTransform.position);
         scaleButtonOriginRectTransform.localScale = new Vector3(1f, distance * 0.004f, 1f);
         Vector3 targetPosition = scaleButtonRectTransform.position;
         Vector3 pos = Vector3.Normalize(targetPosition - scaleButtonOriginRectTransform.position);
         scaleButtonOriginRectTransform.eulerAngles = new Vector3(0f, 0f, Mathf.Atan2(-pos.x, pos.y)) * Mathf.Rad2Deg;
     }
 }

[1]: https://gfycat.com/celebratedpleasantharborporpoise